Access the accompanying videos for this chapter online. Available on ExpertConsult.com .
Treatment of Hirschsprung disease (HD) consists principally of resection of the aganglionic bowel with preservation of the anal sphincter complex. Several operative techniques have emerged over the past 50 years. The proposed advantage of the Duhamel side-to-side anastomosis is the avoidance of dissection of the anterior and lateral part of the distal rectum, preserving the nerve fibers to the adjacent bladder. In the open approach, the Duhamel procedure is a fairly straightforward operation and is known for its good results. Laparoscopically, the procedure is more difficult because it requires intracorporeal suturing of the rectal stump. To date, results with the laparoscopic approach seem promising. This chapter describes our laparoscopic Duhamel technique and documents our results.
Indications and Preoperative Workup
Indications for the laparoscopic Duhamel procedure do not differ from those for the open operation. The diagnosis of HD is determined by rectal suction biopsies. In unclear cases, full-thickness rectal biopsies may be needed, although the biopsy site can interfere with the future location of the side-to-side anastomosis. Alternatively, anorectal manometry can give additional information that is helpful in making the diagnosis of HD. Generally, when a child is referred with suspected HD, rectal washouts (10 to 20 mL/kg each time) are initiated until clear effluent is returned and the abdominal distention has resolved. Parents are then taught to perform the daily rectal washouts at home until the child is admitted for the Duhamel procedure. We prefer to admit our infants and children the day before the operation for further rectal washout.
The infant or child is placed supine on the operating table. Infants are placed transversely at the lower end of a short operating table to allow the surgeon to stand comfortably above the patient’s head. Armrests covered with gel pads on one or both sides of the table allow older children to be positioned similarly. Endotracheal anesthesia is supported by epidural regional anesthesia. Before the procedure, the cleanliness of the rectosigmoid colon is checked by a final rectal washout on the operating table. The patient is prepped from the costal margin down to the lower legs. The legs are covered with separate drapes so they can be moved during the perineal phase of the procedure. The children receive intravenous antibiotics preoperatively and for 24 hours postoperatively. A urinary catheter is inserted after the patient has been draped.
The first 5.5-mm port is placed in the subumbilical fold by a cutdown technique and secured to the fascia with a 2-0 Vicryl (Ethicon Inc., Somerville, NJ) suture. (By tying this suture at the end of the procedure, this subumbilical facial defect is closed.) The 5-mm telescope is then inserted through this cannula. A 3.5- or 5.5-mm port is then introduced in the right lower abdomen under direct vision. A second cannula is then positioned in the right upper quadrant, also for instrumentation. A third port is inserted in the left lower abdomen (LLQ) for introduction of a grasping forceps to elevate and manipulate the bowel. The surgeon and surgical assistant/camera holder stand above the head of the patient.
The operation is started by taking biopsies of the colon for frozen section analysis for ganglion cells ( Fig. 15-1 ). The first biopsy is taken at the visual transition zone, and a second one more proximal in normal-appearing colon. Care is taken to avoid mucosal entry. Vicryl sutures are used to close the biopsy sites. It is advantageous to leave the most proximal suture a little long to mark the site for the subsequent coloanal anastomosis.
Using monopolar cautery, dissection of the aganglionic colon is started on the medial side close to the bowel wall at the level of the rectum by incising the peritoneal attachment and cauterizing the small vessels. When a sufficient mesenteric window has been created, dissection is moved to the patient’s left side, first cauterizing the vessels close to the bowel wall and then opening the peritoneum on the lateral side of the distal colon. In older children, an ultrasonic scalpel can be used to dissect further down the pelvis. At all times, notice should be taken of the location of both ureters and, in boys, the ducti deferentes, which may lie close to this dissection. At the peritoneal reflection in the pelvis, the peritoneum is opened anteriorly to allow more traction on the distal rectum. To preserve nerve fibers running to the bladder, the peritoneum is not extensively dissected inferiorly. Dissection is continued dorsally and laterally to the median hemorrhoidal vessels. The retrorectal space is then opened to facilitate the pull-through of the mobilized bowel ( Fig. 15-2 ). When the retrorectal space has been sufficiently enlarged, the grasping forceps can be palpated from the perineum at the level of the dentate line.
Dissection is then turned upward in the direction of the most proximal biopsy that is positive for ganglion cells, again staying close to the bowel wall. When the mobilization needs to extend higher to the splenic flexure and beyond, the middle colic vessels should be ligated and divided near the aorta. If the aganglionosis extends to the hepatic flexure, the surgeon should consider using the ileocolic artery for the vascular supply to the pull-through colon.
After the colon has been mobilized, a 2-0 Vicryl ligature is placed around the rectum, approximately 3 cm proximal to the peritoneal reflection. A suction device is introduced transanally and the rectum further cleansed. The rectum is elevated with a grasping forceps that has been inserted through the LLQ port. While elevating the rectum, the rectum is sharply transected approximately 2 cm above the peritoneal reflection ( Fig. 15-3 ). In dividing the rectum, first the anterior wall is incised, after which the grasping forceps is used to grasp the anterior wall of the rectum to avoid retraction of the stump. Once the anterior wall of the rectal portion is grasped, the posterior aspect of the rectal wall is incised. A grasping forceps is then introduced through the right midabdominal cannula and positioned in the retrorectal space just proximal to the dentate line.